added @file to the file description header

[mediawiki.git] / RELEASE-NOTES

= MediaWiki release notes =

Security reminder: MediaWiki does not require PHP's register_globals
setting since version 1.2.0. If you have it on, turn it *off* if you can.

== MediaWiki 1.17 ==

THIS IS NOT A RELEASE YET

MediaWiki is now using a "continuous integration" development model with
quarterly snapshot releases. The latest development code is always kept
"ready to run", and in fact runs our own sites on Wikipedia.

Release branches will continue to receive security updates for about a year
from first release, but nonessential bugfixes and feature developments
will be made on the development trunk and appear in the next quarterly release.

Those wishing to use the latest code instead of a branch release can obtain
it from source control: http://www.mediawiki.org/wiki/Download_from_SVN

=== Configuration changes in 1.17 ===
* DatabaseFunctions.php that was needed for compatibility with pre-1.3
  extensions has been removed.
* $wgLogAutocreatedAccounts controls whether autocreation of accounts is logged
  to new users log.
* $wgAllowImageTag can be set to true to whitelist the <img> tag in wikitext.
* (bug 12797) Add $wgGalleryOptions for adjusting of default gallery display
  options.
* $wgAllowUserCssPrefs option allows disabling CSS-based preferences; which can
  improve page loading speed.
* (bug 22858) $wgLocalStylePath is by default set to the same value as
  $wgStylePath but should never point to a different domain than the site is
  on, allowing skins to use .htc files which are not cross-domain friendly.
* (bug 20193) Added $wgVectorShowVariantName global configuration variable
  which causes Vector to render the variants drop-down menu with a label
  showing the current variant name. This is off by default, pending further
  research into its user experience implications.
* Added $wgJQueryVersion, $wgJQueryMinified and $wgJQueryOnEveryPage (true by
  default) to configure loading of jQuery by MediaWiki.
* XmlFunctions.php has been removed. Use the Xml or Html classes as appropriate.
* Added $wgSQLMode for setting database SQL modes - either performance (null)
  or other reasons (such as enabling stricter checks)
* $wgFileStore has been deprecated. The only usage $wgFileStore['deleted'] has
  been turned into $wgDeletedDirectory.
* $wgDeletedDirectory has been added to specify what directory to place deleted
  uploads in.
* IBM DB2 database no longer uses the db specific $wgDBport_db2 variable but the
  normal $wgDBport.
* The upload link for missing files can now be set separately from the
  navigation link with $wgUploadMissingFileUrl.
* $wgCategoryPrefixedDefaultSortkey was removed and is now always false.  This
  provides more sensible sorting behavior for categories.
* Removed unused globals: $wgEnableSerializedMessages, $wgCheckSerialized,
  $wgUseMemCached, $wgDisableSearchContext, $wgColorErrors,
  $wgUseZhdaemon, $wgZhdaemonHost and $wgZhdaemonPort.
* (bug 24408) The include_path is not modified in the default LocalSettings.php
* $wgVectorExtraStyles was removed, and is no longer in use.
* $wgLoadScript was added to specify alternative locations for ResourceLoader
  requests.
* $wgResourceLoaderMaxage was added to specify maxage and smaxage times for
  responses from ResourceLoader based on whether the request's URL contained a
  version parameter or not.
* $wgResourceLoaderDebug was added to specify the default state of debug mode;
  this will still be overridden with the debug URL parameter a la
  $wgLanguageCode.
* $wgResourceLoaderInlinePrivateModules was added to specify whether private
  modules such as user.options should be embedded in the HTML output or
  delivered through a resource loader request, which bypasses server cache (like
  squid) and checks the user parameter against $wgUser. The former adds more
  data to all pages, while the latter adds a request which cannot be cached
  server side.
* Removed $wgUpdates for database updates; extension should use
  DatabaseUpdater::addExtensionUpdate().

=== New features in 1.17 ===
* (bug 10183) Users can now add personal styles and scripts to all skins via
  User:<name>/common.css and /common.js (if user css/js is enabled).
* (bug 22748) Add anchors on Special:ListGroupRights.
* (bug 21981) Add parameter 'showfilename' to <gallery> to automatically
  apply the names of the individual files within the gallery.
* Future-proof redirection to fragments in Gecko, so things work a little nicer
  if they fix <https://bugzilla.mozilla.org/show_bug.cgi?id=516293>.
* Support git:// and mms:// protocols by default for external links.
* (bug 15810) Blocked admins can no longer unblock themselves without the
  'unblockself' permission (which they have by default).
* (bug 18499) Added "enhanced" URL parameter to switch between old and enhanced
  changes list.
* (bug 22925) "sp-contributions-blocked-notice-anon" message now displayed when
  viewing contributions of a blocked IP address.
* (bug 22474) {{urlencode:}} now takes an optional second paramter for type of
  escaping.
* Special:Listfiles now supports a username parameter.
* Special:Random carries over query string parameters.
* (bug 23206) Add Special::Search hook for detecting successful "Go".
* When visiting a "red link" of a deleted file, a deletion and move log excerpt
  is provided on the Upload form.
* (bug 22647) Add category details in search results.
* (bug 23276) Add hook to Special:NewPages to modify query.
* Add accesskey 's' and tooltip to 'Save' button at Special:Preferences.
* Add accesskey 'b' and tooltip to the summary field of edit mode.
* (bug 20186) Allow filtering Special:Contributions for RevisionDeleted edits.
* ajaxwatch now uses the API and JQuery, and can be used to animate arbitrary
  watch links, not just to watch the page the link is on.
* (bug 20976) "searchmenu-new-nocreate" message now displayed when when there
  is no title match in search and the user has no rights to create pages.
* (bug 23429) Added new hook WatchlistEditorBuildRemoveLine.
* (bug 18488) Added maintenance script refreshCategoryCounts.php
* (bug 22844) Added support for WinCache object caching.
* (bug 23580) Add two new events to LivePreview so that scripts can be
  notified about the beginning and finishing of LivePreview actions.
* (bug 21278) Now the sidebar allows inclusion of wiki markup.
* (bug 23733) Add IDs to messages used on CSS/JS pages
* (bug 21312) RevisionMove allows moving individual revisions of a page to
  another page. Introducing 'revisionmove' user right; disabled by default;
  experimental feature.
* Show validity period of the login cookie in Special:UserLogin and
  Special:Preferences
* Interlanguage links display the page title in their tooltip.
* (bug 23621) New Special:ComparePages to compare (diff) two articles.
* (bug 4597) Provide support in Special:Contributions to show only "current"
  contributions
* (bug 17857) {{anchorencode}} acts more like how the parser creates section ids
* (bug 21477) \& can now be used in <math>
* (bug 11641) \dotsc \dotsm \dotsi \dotso can now be used in <math>
* (bug 21475) \mathtt and \textsf can now be used in <math>
* texvc is now run via ulimit4.sh, to limit execution time.
* SQLite now supports $wgSharedDB.
* (bug 8507) Group file links by namespace:title on image pages
* Stop emitting named entities, so we can use <!DOCTYPE html> while still being
  well-formed XML
* texvc now supports \bcancel and \xcancel in addition to \cancel and \cancelto
* Added scriptExtension setting to $wgForeignFileRepos
* ForeignApiRepo uses scriptDirUrl if apiBase not set
* (bug 24212) Added MediaWiki:Filepage.css which is also included on foreign
  client wikis.
* (bug 14685) Double underscore magic word usage is now tracked in the
  page_props table, as well as the behavioral magic words {{DEFAULTSORT}} and
  {{DISPLAYTITLE}}
* (bug 24045) MediaWiki:Ipb-needreblock is now wrapped in a div with class
  "mw-ipb-needreblock"
* (bug 24313) The preference to mark edits minor by default was removed,
  because it encourages edits to be marked minor accidentally and it can be
  easily replicated by custom user scripts for those who really want it.
* Non-file pages can no longer be moved to the file namespace, nor vice versa.
* (bug 671) The <dfn>, <kbd> and <samp> elements have been whitelisted in user
  input
* (bug 24563) Entries on Special:WhatLinksHere now have a link to their history
* (bug 21503) There's now a "reason" field when creating account for other users
* (bug 24418) action=markpatrolled now requires a token
* A variety of category sort-related fixes, including:
** (bug 164) In English, lowercase and uppercase letters now sort the same.
   (This should be expanded to proper sorting for other languages before the
   1.17 release.)
** (bug 1211) Subcategories, ordinary pages, and files now page separately.
** When several pages are given the same sort key, they sort by their names
   instead of randomly.
* (bug 23848) Add {{ARTICLEPATH}} Magic Word.
* JavaScript-based password complexity checker on account creation and
  password change.
* The HTML ID's generated for sections are now much prettier when they contain
  punctuation or non-English letters, so a section named "Hello?" will now
  result in a URL ending in "#Hello?" rather than "#Hello.3F".
* (bug 8140) Add dedicated CSS classes to Special:Newpages elements
* (bug 11005) Add CSS class to empty pages in Special:Newpages
* The parser cache is now shared amongst users whose different settings aren't
  used in the page.
* Any attribute beginning with "data-" can now be used in wikitext, per HTML5.
* (bug 24007) Diff pages now mention the number of users having edited
  intermediate revisions
* Added new hook GetIP
* (bug 16574) Allow administrators to temporarily disable the account creation
  limit for IP addresses: [[MediaWiki:Ratelimit-excluded-ips]]
* Special:Version now displays whether a SQLite database supports full-text
  search.
* (bug 24343) New parser hook {{linkurl:}}, same as {{localurl:}} with fragment
* TS_ISO_8691_BASIC was added as a time format, which is used by ResourceLoader
  for versioning

=== Bug fixes in 1.17 ===
* (bug 17560) Half-broken deletion moved image files to deletion archive
  without updating database.
* (bug 22666) Submitting user block form with an invalid user name no longer
  throws an error.
* (bug 22665, bug 22667) User '0' can now be unblocked and have its block
  settings changed.
* (bug 22606) The body of e-mail address confirmation message is now different
  when the address changed.
* (bug 22664) Special:Userrights now accepts '0' as a valid user name.
* (bug 5210)  Preload parser now parses <noinclude>, <includeonly> and
  redirects.
* (bug 22709) IIS7 mishandles redirects generated by OutputPage::output() when
  the URL contains a colon.
* (bug 22353) Categorised recent changes now works again.
* (bug 22747) "Reveal my e-mail address in notification e-mails" preference is
  now only displayed when relevant.
* (bug 22772) {{#special:}} parser function now works with subpages.
* (bug 18664) Relative URIs in interwiki links cause failed redirects.
* (bug 19270) Relative URIs in interwiki links break interwiki transclusion.
* (bug 22903) Revdelete log entries now show in the user preferred language.
* (bug 22905) Correctly handle <abbr> followed by ISBN.
* (bug 22940) Namespace aliases pointing to main namespace don't work.
* (bug 15810) Blocked admins can no longer block/unblock other users.
* (bug 22876) Avoid possible PHP Notice if $wgDefaultUserOptions is not
  correctly set.
* (bug 14952) Page titles are renormalized after html entities are removed so
  that links with non-NFC character references work correctly.
* (bug 22991) wgUserGroups JavaScript variable now reports * group for
  anonymous users instead of null.
* (bug 22627) Remove PHP notice when deleting a page only hidden users edited.
* (bug 21520) Anonymous previews now also gives a warning about not being
  logged in (anonpreviewwarning).
* (bug 22935) image/x-ms-bmp mime type added for BMP files.
* (bug 23024) Special:ListFiles now escapes file names correctly.
* (bug 22867) "View source" tab is now only displayed if there's source text.
* (bug 19393) Feeds now format dates in user language rather than content
  language.
* (bug 22852) "Served in" comment is now the time used to cache a single page
  when using rebuildFileCache.php
* (bug 22496) Viewing diff of a redirect page without specifying "oldid".
  parameter no longer makes the page displayed as being the redirect target.
* (bug 22918) Feed cache keys now use $wgRenderHashAppend.
* (bug 21916) Last-Modified header is now correct when outputting cached feed.
* (bug 20049) Fixed PHP notice in search highlighter that occurs in some cases.
* (bug 23017) Special:Disambiguations now list pages in content namespaces
  rather than only main namespace.
* (bug 23063) $wgMaxAnimatedGifArea is checked against the total size of all
  frames, and $wgMaxImageArea against the size of the first frame, rather than
  the other way around.  Both now default to 12.5 megapixels.  Also, images
  exceeding $wgMaxImageArea can still be embedded at original size.
* (bug 23078) "All public logs" option on Special:Log is now always the first
  item.
* (bug 16817) Group names in user rights log are now singular and in lowercase.
* Special:Preferences no longer crashes if the wiki default date formatting
  style is not valid for the user's interface language.
* (bug 23167) Check the watch checkbox by default if the watchcreations
  preference is set.
* Maintenance script cleanupTitles is now able to fix titles stored
  in a negative namespace (which is invalid).
* (bug 19858) Removed obsolete <big> in interface messages.
* (bug 21456) "Bad title" error when showing non-local interwiki pages no longer
  displays incorrect tabs.
* (bug 23190) Improved math representation for text browsers.
* (bug 22015) Improved upload-by-url error handling and error display.
* (bug 17941) $wgMaxUploadSize is now honored by all upload sources.
* (bug 23080) New usernames now limited to 235 bytes so that custom skin files
  work.
* (bug 23075) Correct MediaTransformError default width in gallery.
* (bug 16487) The Anonymous user account used on Postgres is no longer
  displayed on Special:Listusers.
* (bug 23313) Move watchlisthidepatrolled above token in watchlist preferences
  to enhance preference grouping.
* (bug 23298) Interwiki links with prefix only in log summaries now link to the
  correct link.
* (bug 23284) Times are now rounded correctly.
* (bug 23375) Added ogv, oga, spx as extensions for ogg files.
* (bug 18408) All required permissions for uploading (upload, edit, create)
  are now checked when loading Special:Upload. Toolbar link for Special:Upload
  is no longer shown if the user does not have the required permissions.
* (Bug 23397) texvc in html mode renders \sim as &tilde; not &sim;
* (Bug 23241) Remove License selector, because it is not used when uploading a
  new version.
* (bug 23240) Add ID to namespace selector form on Special:Watchlist.
* The pipe | character in urls is now escaped.
* (bug 23422) mp3 files can now be moved.
* (bug 23448) MediaWiki:Summary-preview is now displayed instead of
  MediaWiki:Subject-preview when previewing summary.
* (bug 23426) The {{REVISIONMONTH}} variable is now zero-padded and added
  new variable {{REVISIONMONTH1}} when unpadded version is needed.
* Special:Userrights didn't recognize user as changing his/her own rights if
  user did not capitalize first letter of username.
* (bug 23507) Add styles for printing wikitables.
* (bug 19586) Avoid JS errors in mwsuggest when using old browsers such
  as Opera 8.
* (bug 23563) Old skins now support $wgUploadNavigationUrl and take into
  account upload rights.
* (bug 1347) Render \phi in math using images, in order to create consistent
  and correct render results.
* (bug 16573) Render \epsilon in math using images, in order to create
  consistent and correct render results.
* (bug 22541) Support image redirects when using ForeignAPIRepo.
* (bug 22967) Make edit summary length cut-off behave correctly for
  multibyte characters.
* (bug 8689) Long numeric lines no longer  kill the parser.
* (bug 23740) Article::doRedirect() now use $extraQuery parameter correctly if
  the $noRedir parameter is set to true
* (bug 23688) Correct mime types for Office 2007 OpenXML documents.
* (bug 23787) Corrected $wgDefaultSkin's comment in DefaultSettings.php
* (bug 23797) Xml::input() now allows '0' for the value parameter
* (bug 23747) Make sure that on History pages, the RevDel button is not
  accidently activated when hitting enter.
* (bug 23845) Special:ListFiles now uses correct file names without underscores
* Ask for permanent login in Special:Preferences only if $wgCookieExpiration > 0
* (bug 16356) Repair dumpInterwiki.inc to use proper normalization.
* (bug 24006) deleteArchivedRevisions.php maintenance script now longer throws
  a fatal error
* (bug 23465) Don't ignore the predefined destination filename on
  Special:Upload after following a red link
* Correct the escaping of the autosummary URI fragments.
* (bug 23642) Recognize mime types of MS OpenXML documents.
* (bug 22784) Normalise underscores and spaces in autocomments.
* (bug 19910) Headings of the form ===+\s+ are now displayed as valid headings
* (bug 24022) Only check file extensions on the uploadpage when needed.
* (bug 24076) Recognize Office 2003 files with OpenXML trailers
* (bug 24244) Updated comments in DefaultSettings.php to reflect
  Image: --> File: namespace rename.
* Make wfTimestamp recognize negative unix timestamp values.
* (bug 24401) SimpleSearch: No button/text indicating 'Search' if image is
  disabled
* (bug 23293) Do not show change tags when special:recentchanges(linked)
  or special:newpages is transcluded into another page as it messes up the
  page.
* (bug 24517) LocalFile::newFromKey() and OldLocalFile::newFromKey() no longer
  throw fatal errors
* (bug 23380) Uploaded files that are larger than allowed by PHP now show a
  useful error message.
* Uploading to a protected title will allow the user to choose a new name
  instead of showing an error page
* (bug 24425) Use Database::replace instead of delete/insert in
  SqlBagOStuff::set to avoid query errors about duplicate keynames.
* (bug 15470) First letters of filenames are always capitalized by upload JS.
* (bug 21215) NoLocalSettings.php doesn't tolerate rewrite rules
* (bug 21052) Fix link color for stubs in NewPages
* (bug 24714) Usage of {{#dateformat: }} in wikis without $wgUseDynamicDates no
  longer pollutes the parser cache.
* (bug 17031) Correct which characters the parser allows in tag attributes.
* Save 200 useless queries on each category page view
* Shell commands will now work on Linux in filesystems mounted noexec
* (bug 24804) Corrected commafying in Polish and Ukrainian
* "Difference between pages" is now displayed instead of "Difference between
   revisions" on diffs when appropriate.
* (bug 23703) ForeignAPIRepo fails on findBySha1() when using a 1.14 install as
  a repository due to missing 'name' attribute from the API list=allimages
* (bug 24898) MediaWiki uses /tmp even if a vHost-specific tempdir is set, also
  make wfTempDir() return a sane value for Windows on worst-case
* (bug 24824) Support ImageMagick 6.5.6-2+ JPEG decoder size hint, to reduce
  memory usage when such an ImageMagick is used for scaling.
* Disable multithreaded behaviour in recent ImageMagick, to avoid a deadlock
  when a resource limit such as $wgMaxShellMemory is hit.
* (bug 24981) Allow extensions to access SpecialUpload variables again
* (bug 20744) Wiki forgets about an uploaded file
* (bug 17913) Don't show "older edit" when no older edit available
* (bug 6204) TOC not properly rendered when using $wgMaxTocLevel
* (bug 24977) The accesskey in history page now lead directly to the diff 
  instead of alterning focus between the two buttons.
* (bug 24987) Special:ListUsers does not take external groups into account
* (bug 20633) update.php has mixed language output
* SQLite system table names are now never prefixed.
* (bug 25292) SkinSubPageSubtitle hook now passes the Skin object as second
  parameter
* (bug 25167) Correctly load JS fixes for IE6 (fixing a regression in 1.16)
* (bug 25367) wfShellExec() is more explicit when failing due to disabled
  passthru()

=== API changes in 1.17 ===
* (bug 22738) Allow filtering by action type on query=logevent.
* (bug 22764) uselang parameter for action=parse.
* (bug 22944) API: watchlist options are inconsistent.
* (bug 22868) don't list infinite block expiry date as "now" in API logevents.
* (bug 22290) prop=revisions now outputs "comment" field even when comment.
  is empty, for consistency with list=recentchanges.
* (bug 19721) API action=help should have a way to just list for a specific
  module.
* (bug 23458) Add support for pageid parameter to action=parse requests.
* (bug 23460) Parse action should have a section option.
* (bug 21346) Make deleted images searchable by hash.
* (bug 23461) Normalise usage of parameter names in parameter descriptions.
* (bug 23548) Allow access of another users watchlist through watchlistraw
  using token and username.
* (bug 23524) Api Modules as followup to bug 14473 (Add iwlinks table to
  track inline interwiki link usage.
* Add pltitles and tltemplates to prop=links and prop=templates respectively,
  similar to prop=categories's clcategorie
* (bug 23834) Invalid "thumbwidth" and "thumbheight" in "imageinfo" query when
  thumbnailing larger than original image
* (bug 23835) Need "thumbmime" result in "imageinfo" query
* (bug 23851) Repair diff for file redirect pages
* (bug 24009) Include implicit groups in action=query&list=users&usprop=groups
* (bug 24016) API: Handle parameters specified in simple string syntax
  ( 'paramname' => 'defaultval' ) correctly when outputting help
* (bug 24089) Logevents causes PHP Notice if leprop=title isn't supplied
* (bug 23473) Give description of properties on all modules
* (bug 24136) unknownerror when adding new section without summary, but
  forceditsummary
* (bug 16886) Sister projects box moves down the extract of the first result
  in IE 7.
* (bug 22339) Added srwhat=nearmatch to list=search to get a "go" result
* (bug 24303) Added new &servedby parameter to all actions which adds the
  hostname that served the request to the result. It is also added
  unconditionally on error
* (bug 24185) Titles in the Media and Special namespace are now supported for
  title normalization in action=query. Special pages have their name resolved
  to the local alias.
* (bug 24296) Added converttitles parameter to convert titles to their
  canonical language variant.
* (bug 17398) Fixed "link" parameter in image links with "thumb" or "frame"
  parameter.
* (bug 23936) Add "displaytitle" to query/info API
* (bug 24485) Make iwbacklinks a generator, optionally display iwprefix and
  iwtitle
* (bug 24564) Fix fatal errors when using list=deletedrevs, prop=revisions or
  one of the backlinks generators with limit=max.
* (bug 24656) API's parse module needs option to disable PP report
* PARAM_REQUIRED parameter flag added. If this flag is set, and the end user
  does not set the parameter, the API will automatically throw an error.
* (bug 24665) When starttimestamp is not specified, fake it by setting it to
  NOW, not to the timestamp of the last edit
* (bug 24677) axto= parameters added to allcategories, allimages, alllinks,
  allmessages, allpages, and allusers
* (bug 24236) Add add, remove, add-self, remove-self tags to
  meta=siteinfo&siprop=usergroups
* (bug 24484) Add prop=pageprops module
* (bug 24330) Add &redirect parameter to ?action=edit
* (bug 24722) For list=allusers&auprop=blockinfo, only show blockedby and
  blockreason if the user is actually blocked.
* Add format=dump and format=dumpfm, outputs results in PHP's var_dump() format
* For required string parameters, if '' is provided, this is now classed as
  missing
* (bug 24724) list=allusers is out by 1 (shows total users - 1)
* (bug 24166) API error when using rvprop=tags
* Introduced "asynchronous download" mode for upload-by-url. Requires 
  $wgAllowAsyncCopyUploads to be true.
* sinumberingroup correctly gives size of 'user' group, and omits size of
  implicit groups rather than showing 0.
* (bug 25248) API: paraminfo errors with certain modules

=== Languages updated in 1.17 ===

MediaWiki supports over 330 languages. Many localisations are updated
regularly. Below only new and removed languages are listed, as well as
changes to languages because of Bugzilla reports.

* Moroccan Spoken Arabic (ary) (new)
* Banjar (bjn) (new)
* Danish (dk) (removed deprecated language code)
* Fiji Hindi (Devangari script) (removed)
* Kabardian (kdb) (new, dummy)
* Kabardian (Cyrillic) (kbd-cyrl) (new)
* Latgalian (ltg) (new)
* Minangkabau (min) (new)
* Dutch (informal) (nl-informal) (new)
* Rusyn (rue) (new)

* (bug 23156) Commafy and search normalization updated for Belarusian
  (Taraškievica).
* (bug 23283) Native name for Old English -> Ænglisc.
* (bug 23364) Native name for Azerbaijani -> Azərbaycanca.
* (bug 24593) Native name for Sorani now uses only Arabic script.
* (bug 24628) Generic translations for NS_USER/NS_USER_TALK for Esperanto.
* (bug 24917) Polish as fallback for Kashubia.
* (bug 24794) Tatar link trail updated.

== Compatibility ==

MediaWiki 1.17 requires PHP 5.1 (5.2 recommended). PHP 4 is no longer
supported.

MySQL 3.23.x is no longer supported; some older hosts may need to upgrade.
At this time we still recommend 4.0, but 4.1/5.0 will work fine in most cases.


== Upgrading ==

1.17 has several database changes since 1.16, and will not work without schema
updates.

If upgrading from before 1.11, and you are using a wiki as a commons reposito-
ry, make sure that it is updated as well. Otherwise, errors may arise due to
database schema changes.

If upgrading from before 1.7, you may want to run refreshLinks.php to ensure
new database fields are filled with data.

If you are upgrading from MediaWiki 1.4.x or earlier, some major database
changes are made, and there is a slightly higher chance that things could
break. Don't forget to always back up your database before upgrading!

See the file UPGRADE for more detailed upgrade instructions.


=== Caveats ===

Some output, particularly involving user-supplied inline HTML, may not
produce 100% valid or well-formed XHTML output. Testers are welcome to
set $wgMimeType = "application/xhtml+xml"; to test for remaining problem
cases, but this is not recommended on live sites. (This must be set for
MathML to display properly in Mozilla.)

For notes on 1.16.x and older releases, see HISTORY.


=== Online documentation ===

Documentation for both end-users and site administrators is currently being
built up on MediaWiki.org, and is covered under the GNU Free Documentation
License (except for pages that explicitly state that their contents are in
the public domain) :

  http://www.mediawiki.org/wiki/Documentation


=== Mailing list ===

A MediaWiki-l mailing list has been set up distinct from the Wikipedia
wikitech-l list:

  http://lists.wikimedia.org/mailman/listinfo/mediawiki-l

A low-traffic announcements-only list is also available:

  http://lists.wikimedia.org/mailman/listinfo/mediawiki-announce

It's highly recommended that you sign up for one of these lists if you're
going to run a public MediaWiki, so you can be notified of security fixes.


=== IRC help ===

There's usually someone online in #mediawiki on irc.freenode.net